Arctic greening and its climate change feedback: cascading long-term effects of above- and belowground linkages

This SPI Exploratory Grant is aimed at equipping the ALTER experiment (Abisko, Sweden) for long-term monitoring of belowground vegetation and microbial dynamics. Specifically, we aim to peek into the "black box" of arctic soils and monitor non-destructively and at high spatial and temporal resolution the dynamics of fine root and hyphae production, phenology and turnover. We are convinced that this is of primary importance as in the Arctic up to 80% of living plant biomass is found belowground and fine root and microbial turnover represent a major sink of terrestrial net primary productivity. To this end, we will install minirhizotrons as the primary tool to study root dynamics in the field, micromesh exclosures to partition root vs. hyphae contribution to soil processes, in-growth bags to quantify fungal hyphae production and composition, litterbags to quantify soil organic matter decomposition vs. stabilisation, and genetic markers to assess soil microbial diversity.